Device for casting sheet-glass.



No. 653,849. Patented July l7, I900.

J. W. SHEPPARD.

DEVICE FOR CASTING SHEET GLASS.

(Application filed Oct. 13, 1899.)

(No Model.) 2 Sheets-Sheet l.

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Patented July l7, I900.

J. W. SHEPPARD. DEVICE FOR CASTING SHEET GLASS.

(Application filed Oct. 13, 1899.)

2 Sheats$haet 2.

(No Model.)

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P TENT Orin,

JOSEPH W. SHEPPARD, OF NEW YORK, N. Y,

Device FOR CASTING SHEET-GLASS.

mummies forming part of Letters Patent No. 653,849, dated July 1%, 19cc.

Application filed omter'ls, 1999'. semi No. 733,467. (No model.)

T (all whom, it may concern:

Be it known that I, J OSEPH W. SHEPPARD, a citizen of the United States,residing in the city, county, and State of New York, have invented a newand useful Improvement in Devices for Casting Sheet-Glass, of which the1 following is a specification.

My invention relates especially to the making of sheet-glass, and hasfor its object the provision of means for forming the same by casting.

To attain the desired end my invention consists in certain novel anduseful combinations or arrangements of parts and peculiarities ofconstruction and operation, all of which will be hereinafter first fullydescribed and then pointed out in the claims.

In carrying my invention into effect I cast the glass between sheets orwalls of metal or other suitable material having smooth or polishedsurfaces if transparent glass is desired or ribbed or embossed surfacesif figured or translucent glass is desired, these sheets of metal ormolds being so adjusted in relation to each other upon aproperly-constructed platform provided with runninggear that there isspace between the sheets forming the molds for the application of heatnot only before the glassis brought in contact with the molds, but alsoduring the time consumed in casting and for some time thereafter,according to the requirements of the annealing process, which takesplace in the molds.

The sheets of metal forming the group of molds, located side by side,are so arranged that the spaces for the reception of the molten glassare open at the top and closed at the sides and bottom, while theheating-chambers located on each side of the molds are closed allaround, provision being made for the proper ventilation, according tothe requirements of the process of heating. Y

The sheets'forming the molds maybe of any size desired and so adjustedas to admit of the formation of a sheet of glass of any desiredthickness, even varying in thickness or design in the same group orseries, and twenty, more or less, may constitute a group, according tothe size of the truck that carries them or the platform upon which theyare assembled. They are firmly held together in any efficient manner,and the whole group then constitutes virtually a solid mass of sheets,and as the heat is very evenly distributed and is kept around the groupof molds by a cover or hood made of suitable material it is plainly seenthat the warping of the sheets of glass is simply impossible. The hoodor cover may be made of the proper dimensions to fit over a certain-sizegroup of molds and to entirely envelop them during the process ofheating some time before the casting of the glass, and when the group ofmolds has been heated to the desired degree the truck upon which thegroup of molds rests is pushed along the track to a suitable place nearthe furnace, when the molten glass is poured in through an opening inthe cover or hood, and the molten glass so poured on the top of themolds surrounded by an intensely-hot atmosphere gradually fills all theopen spaces, sinking into the hot molds by gravitation until they arefilled. Then the truck, with the process of heating still going on, canbe pushed back to the place from which it was taken and the process ofan-.

nealing consummated by the gradual reduction of heat until at last noartificial heat is applied, and when the molds are cooled and the hoodor cover lifted the sheets of glass are removed.

According to the capacity of the furnace a number of trucks upon whichthe groups of molds are placed can be used, each truck standing upon itsown switch connected with the track that leads to the furnace from whichthe molten glass is obtained, whereby there is great economy of time andlabor gained.

By my presentinvention the air in the molds so constructed and heatedbecomes so rarefied before the molten glass is poured in that there isvirtually none left of sufficient density to affect the glass. Hence itof necessity follows that there are no air-bubbles in sheets of glasscast by this method, and as the surfaces of the molds so formed will beof even and great temperature, regulated at will, the molten glass willretain its plastic state until it has evenly filled the molds. Hencedoes my invention entirely overcome the aforementioned defects of theprocesses now in use, which produce sheets of glass of uneven thickness.Thus it is seen that my invention produces sheets of glass withouteither air-bubbles, uneven thicknesses, or warping, and inadditionthereto it will produce sheets of glass having as smooth andpolished a surface as 5 that of the molds in which it is cast, thereforeproducing clear and transparent glass of any dimensions or thicknesswithout the use of the grinding-wheels or polishing-tables and at nomore cost than what is necessary for me to produce translucent orfigured glass. Likewise as the glass will be kept in a plastic stateuntil it has entirely filled the molds, and so is kept from coming incontact with cooler air or metal to prematurely chill it in part or inwhole, it follows that the sheets of glass made in accordance withmyinvention will never be known as lappy glass and v will be of evencutting quality throughout, thus avoiding the possibility of producingthe hard-cutting sheets, also the lappy glass, that so often are theresult of the processes heretofore known.

As hot metal and molten glass adhere to each other when brought in closecontact, it

'2 5 might at first sight appear that this fact would be an impedimentto the practical working of my invention; but experience shows thatthough the two adhere while they are in a heated state they willseparate by natural con- 0 traction of the metal as the heat gets less,and as the molds are kept to a great heat for some time after the moltenglass has been dumped or allowed to fiow into the space at the top ofthe group or series of heated molds under 3 5 the hood or cover theglass will not therefore prematurely harden, but being kept for sometime in a plastic state will be free to seek its level by the law ofgravitation, so the molds will be filled to their full capacity, and the40 product will of necessity be of a superior quality, yet produced at agreatly-reduced cost. Likewise, in addition thereto, there is also astill further economy in the practical utilization of my invention, asit entirely dispenses with the annealing-oven and the labor required tooperate it.

In the accompanying drawings, forming a part hereof, Figure 1 is a planview of a device designed for carrying my invention into efiect. Fig. 2is an end elevation thereof. Fig. 3 is an enlarged vertical sectionalview through a part of the molds at line a: a; of Fig. 1.

Similar numerals of reference wherever they occurindicate correspondingparts in all the 5 is a flexible gas pipe or hose from any source ofgas-supply leading to a distributing- 1 pipe 6, fixed to the truck-body.

'7 are branch pipes which conduct the gas from the supply 6 to burningdevices Bin the flooring 4, the flow to the branch pipes being regulatedby means of valves 9, and air to support combustion is admitted throughperforations (indicated by the dotted lines) through the sections offlooring 4.

10 are plates preferably made of steel and in the case of use for makingtransparent glass having their faces highly polished.

11 are removable caps the shape of an inverted V, which fit over andrest upon each pair of plates 10. At the bottom each plate 10 fits intoa groove in one of the floor-sections 4 and at each side into grooves insectional supporting-pieces 12, which in turn are held in place by aplate 13, which may be the entire length of the series of molds or madein parts, as desired.

14: is a sustaining-bracket, one of these being placed at each side of aseries or group of molds.

15 is a hood. This hood is arranged to completely envelop the molds andis provided at top with a door 16 for the supply of molten glass, asindicated in Fig. 1 of the drawings, and with lifting-rings 17.

In assembling the molds for use the floorsections 4 are first placed inposition upon the truck or platform. Two plates 10 are then set up inthe grooves therein next to a bracket 14, and a section 12 of thesupport is placed at each end of the plates, and a cap 11 over the topof the two plates. Side plates 13 are placed against the first sectionof the series or group of molds so commenced, these side plates 13 beingdrawn along the supportingplatform until the entire group of molds iscompleted, when the parts are wedged together between the brackets 14.It will be observed that a space is left between each two of the plates10, this space being closed at the bottom and ends and open at the top,forming a mold for a sheet of glass. The hood or cover 15 is now placedin position overthe completed series or group of molds and the gas isignited within the hollow spaces between the molds, forming the wallsthereof, and the molds are heated to the desired deree.

I have shown my invention as arranged for heating by the combustion ofgas; but it is obvious that electricity might be employed as a heatingmedium, if desired, as I do not limit myself to any specific means ofheating the molds.

a Whpn the molds are brought to the proper degree of heat, the truck isrun to the source of supply of molten glass, which is caused to flowinto the space at the top of the molds and over the upper extremities ofthe heated ICC walls, finding its way down into the spaces being theseries of molds is run to any convenient point and the heat graduallydecreased 7 by properly regulating the amount of gas consumed until thesupply is entirely out ofif, permitting the molds and contained glass tocool to the temperature of the atmosphere, thus annealing the glasswithin the molds without any handling whatever, when it is removed byseparating the sections of the molds, being in proper condition forimmediate use or shipment. The molds are new again assembled and kept inuse continuously, if desired, and any number of trucks having groups ofmolds upon them can thus be em ployed to the full capacity ofthefurnace.

Having now fully described my invention, what I claim as new therein,and desire to secure by Letters Patent, is-

1. A built-up, separable mold for casting sheet-glass consisting of twoparallel plates of polished metal; divided end and bottom pieces withwhich said plates. engage, and means for applying heat to the mold incom- 1 bination with an enveloping hood or cover,

gage; and means for applying heat to the said plates, in combinationwith a support upon which said mold is assembled and secured.

3. In a device of the character herein specified, a group or series ofmolds in which are comprised a plurality of parallel plates forming thesides of the molds; divided end and bottom pieces with which said platesengage; sloping caps arranged to fit over each pair of plates betweenthe molding-spaces and below the tops of the end pieces, in combinationwith means for applying heat to the molds, substantially as shown anddescribed.

4:. A group or series of separable molds; means for securing said moldstogether; means for heating said molds, and regulating the temperaturethereof; a hood or cover for enveloping said molds, and a supportingtruck or platform, the whole combined and arranged substantially asshown and described.

Signed by me at New York, N. Y. this 11th day of October, 1899.

JOSEPH W. SHEPPARD.

WVit-nesses:

A. M. PIERCE, LESTER L. SIssoN.

